1. Field of the invention
This invention relates to an electrical device and a receptacle for accommodating the device. The invention is particularly, but not exclusively, concerned with electrical circuit protection devices such as fuses, circuit breakers or the like.
2. Description of the prior art
Electrical circuit protection devices such as cartridge fuses and circuit breakers that are designed to be mounted in respective receptacles by insertion of pins must provide predetermined breaking characteristics depending upon the nominal current carried by an associated electrical circuit. To properly protect an associated electrical circuit, a particular circuit protection device should not be interchangeable (or at least should have a limited degree of interchangeability) with other devices having different breaking characteristics.
Known techniques of preventing such interchangeability suffer from the disadvantage that they require differently sized electrical devices and differently sized respective receptacles therefor. This means that the manufacturer must establish a very large and expensive production facility for producing a range of devices and receptacles of different sizes, so that production costs are high. Further, installers have to stock a large number of different, very expensive devices and receptacles, which necessitates a large capital investment.